Power transfer system for a four-wheel drive vehicle

摘要

The present invention provides a power transfer system for a four-wheel drive vehicle which permits the vehicle operator to choose between operation in two-wheel drive and part-time four-wheel drive modes or an "on-demand" four-wheel drive mode. The power transfer system is adapted for use in conjunction with automatic disconnect-type drivelines and is operable for disabling the on-demand four-wheel drive feature upon the vehicle operator subsequently shifting into any of the two-wheel drive and part-time four-wheel drive modes.